JP2692097B2 - Scroll gas compressor - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to oil injection in scroll gas compressors.
Regarding the passage. 2. Description of the Related Art A scroll compressor has a suction chamber outside the spirally wound compression chamber.
There is a discharge port at the center of the spirally wound compression chamber.
It is provided with a reciprocating compressor or rotary
Needs a discharge valve to compress fluid such as a rotary compressor
If the compression ratio is constant, the discharge pulsation is relatively small.
It is generally known that it does not require a large discharge space
I have. However, especially when compressing gas, the leakage of the compression part
The dimensional accuracy of the spiral part is extremely high in order to reduce the gap.
However, the complexity of the shape of the part and the dimensional accuracy
The cost of the scroll gas compressor is high due to rattling.
However, there was a problem that there was a large variation in performance. Therefore, as a measure to solve this kind of problem, compression
A seal that uses a lubricating oil film to prevent gas leakage on the way
Due to the effect, the dimensional accuracy of the spiral part is optimized and the compressor performance is improved.
It is expected that stabilization will occur, and as shown in Fig. 14,
Lubricating oil at the bottom of the exit chamber directly flows into the compression chamber during compression
A configuration is being considered. In the figure, the motor 703 is arranged in the upper part in the closed case 701,
The compression part is placed in the lower part, and the space 702 in the closed case is the discharge chamber.
With this structure, the lubricating oil in the oil sump 710 at the bottom of the discharge chamber is fixed.
Symmetrical arrangement via each oil suction pipe 722 arranged on the crawl
Directly flow into each hydraulic chamber 723 under compression
(JP-A-57-8386). In addition, another configuration shown in Fig. 15 is also conceivable.
Back pressure chamber 817 and compression chamber provided on the side opposite to the compression chamber of scroll 801
Swirl through a through hole 818 that has a throttling effect that directly communicates with 809
Below the motor 816 installed on the scroll 801 and communicating with the discharge chamber 812
Of the main shaft where the lubricating oil of the oil sump 899 of the section is provided in the crankshaft 807.
Oil holes 719, 920, 921 facing each other, each shaft that slides with the crank shaft 807
Back pressure chamber 81
7 and then flowed into the compression chamber 809 through the through hole 818.
And seal the oil film in the compression chamber. On the other hand, the discharge pressure equivalent to the discharge pressure guided to the upper end of the drive shaft 807
Lubricating oil and lubricating oil in the intermediate pressure state supplied to the back pressure chamber 817
Press the orbiting scroll 801 against the fixed scroll 802 side with
Then, the axial minute gap of the compression chamber 809 is maintained. The lubricating oil in the back pressure chamber 817 is fixed to the orbiting scroll 801.
While lubricating the sliding contact surface with the constant scroll 802, the compression chamber 809
It also flows into the suction chamber located outside and is compressed with the suction gas.
Transferred to the compression chamber 809 and used to seal the oil film in the compression chamber gap
The configuration (Japanese Patent Laid-Open No. 59-110884). Problems to be Solved by the Invention However, it is equal to the discharge pressure as shown in FIG. 14 above.
Compress the lubricating oil in the oil sump 710 at the bottom of the space 702 in the closed case.
Direct differential pressure to the compression chamber 723 on the way via a short throttle passage.
In the case of the inflow configuration, the compression chamber 723 and the oil sump 710 are always directly
Because of the communication structure, the scroll compression method requires a discharge valve.
Closed cycle due to fluid compression without
Cold start of a scroll compressor connected to the piping system for operation
For a while afterwards, the space inside the sealed case 7 rather than the compression chamber 723
The oil sump 710 of 02 is in a lower pressure state and the compression of the compression chamber 723 is compressed.
On the way, the gas flows back into the oil sump 710. As a result, the oil in the oil reservoir 710
The lubricating oil is diffused by the backflow gas from the compression chamber 723 and is discharged.
Along with the discharged gas, it flows out to the compressor external piping system, and the oil sump 710 is moistened.
Lack of lubricating oil occurs. Therefore, wait a while after the compressor starts.
The pressure in the space 702 in the closed case rises and the pressure in the compression chamber 723 rises.
Even if the pressure is higher than the force, the lubricating oil will
Until the oil is supplied to the compression chamber 723 until it is collected in 710
There is no oil film sealing effect in the compression chamber gap, conversely, in the sealed case
The gas in the space 702 flows into the compression chamber 723, resulting in remarkable compression efficiency.
Axis due to decrease, abnormal temperature rise, abnormal pressure rise in compression chamber, etc.
There is a problem in that durability of the sliding receiving portion is deteriorated. In addition, the compression chamber 809 and the back pressure chamber 817 as shown in FIG.
In the configuration that directly communicates with the
Immediately after starting, for a while, it leads to the compressor external piping system
Pressure in discharge chamber 812 leads to compression chamber 809 and compression chamber 809
The pressure is lower than that of the back pressure chamber 817, and gas is conducting during compression.
Hole 818, back pressure chamber 817, bearing gap of drive shaft 807, main shaft direction
Back into the sump via oil holes 719, 720, 721 of the
As in the case, the lubricating oil in the oil reservoir is diffused, and in some cases
The lubricating oil flows out of the compressor together with the discharged gas. Also, the back
The lubricating oil stored in the bearings of the pressure chamber 817 and the drive shaft 807 also flows.
Lubrication of the back pressure chamber 817 at the start of cold start
Main cause of deterioration of durability due to insufficient lubrication of the bearing of drive shaft 807
It was also. Also, abnormal pressure rise due to liquid compression etc. in the compression chamber 809.
However, even if the compression load increases suddenly, the lubricating oil will flow out in the same manner as above.
Occurs, and leads to the compression chamber 809 through the conduction hole 818.
Since the back pressure chamber 817 also has an abnormal pressure rise, the orbiting scroll 801
Is strongly pressed against the fixed scroll 802, and the sliding surface wears.
Low durability due to input loss due to rubbing and abrasion and lack of lubricating oil
There were problems such as inviting the bottom. The compressor is installed in the heating operation refrigeration cycle piping system.
When temporarily switching from heating operation to defrosting operation,
The suction side of the compressor is at high pressure and the discharge side is at low pressure.
In some cases, suction side or compression chamber 809 to back pressure chamber 817
Refrigerant gas flows backward to
Invite below. Therefore, the present invention is to supply oil from the discharge chamber oil reservoir to the compression space.
Backflow from the compression space by providing backflow prevention means in part of the passage
While moving, it moves axially due to the pressure of the backflow gas
Axial compliance mechanism of thrust bearing
By configuring to support overload reduction operation by
The purpose is to improve durability. Means for Solving Problems In order to solve the above problems, scroll gas pressure of the present invention
The compressor is a main frame with a main bearing that supports the drive shaft.
The orbiting scroll is placed between the fixed scroll and
The orbiting scroll lap support disc is
The slides installed on the body frame to support the anti-compression chamber side.
An oil film can be formed between the strike bearing and the end plate of the fixed scroll.
It is arranged with a very small gap and is located on the outer periphery adjacent to the thrust bearing.
Is a mirror plate and a body frame to store the lap support disk.
Is formed and discharge pressure acts on the discharge chamber oil reservoir.
Place the outer peripheral space away from each other and
Rotate inward from the compression chamber side and separated from the thrust bearing.
A back pressure chamber for the orbiting scroll is provided adjacent to the main bearing, and the discharge chamber
The oil reservoir and the compression space pass through the back pressure chamber and the outer peripheral space in order.
The oil between the back pressure chamber and the outer peripheral space communicates with the differential pressure oil supply passage.
Allows only the back pressure chamber to flow into the outer space in the middle of the road
With the check valve device installed,
Between the thrust bearing and the body frame
The biasing means that biases the strike bearing in the direction of the fixed scroll
Provided, orbiting scroll is fixed scroll and thrust bearing
A small gap in the axial direction that allows at least an oil film to be formed between
The thrust bearing is swivel scroll
The thrust provided with means for restricting the range of movement toward the side
Outer space with bearing axial compliance mechanism
Pressure is applied to the thrust bearing toward the anti-compression chamber side,
A part of the wall surface of the outer peripheral space is configured in the strike bearing.
is there. Effect The present invention has the above-described configuration so that the lubricating oil in the discharge chamber oil reservoir is not
Differential pressure oil is supplied to the compression space via the peripheral space, and its path
Moisture of the sliding contact surface between the thrust bearing and the end plate in the outer peripheral space on the way
Used to seal the oil film in the sliding and compression chamber gaps, and
Gas leakage during contraction can be reduced. In addition, the pressure in the compression space rises abnormally and the gas in the compression space
Tries to flow backwards toward the back pressure chamber and discharge chamber oil sump,
Backflow of gas to the back pressure chamber is prevented, and
Thrust bearing retracts to the side opposite the compression chamber due to pressure increase
Be supported. As a result, the orbiting scroll is
It becomes easy to separate from the roll in the axial direction, reducing overcompression.
it can. Example Hereinafter, with respect to the scroll compressor of the example of the present invention,
This will be described with reference to the drawings. In FIG. 1, 1 is an iron-made sealed case, inside of which
The whole becomes a high-pressure atmosphere that communicates with the discharge chamber 2, and the upper part
The rotor 3a of the motor 3 has a compressor 3 arranged at the bottom thereof.
The body frame 5 of the compression part which supports the fixed drive shaft 4.
Makes the interior of the closed case 1 into a motor chamber 6 and a discharge chamber 2.
It is partitioned. The body frame 5 is made lighter and the heat of the bearing is reduced.
Aluminum alloy with excellent heat conduction characteristics mainly for divergence
The iron liner 8 is made of gold and has excellent weldability on the outer periphery.
It is shrink-fitted and fixed, and the outer peripheral part of the liner 8 is sealed in the closed case 1.
It is inscribed all around and welded and partially fixed. The outer peripheral portions of both ends of the stator 3b of the motor 3 are attached to the sealed case 1.
By the inwardly fixed bearing frame 9 and body frame 5,
Supported and fixed. The drive shaft 4 is attached to the bearing frame 9.
Provided on the upper bearing 10 and the upper end of the body frame 5 provided
The lower bearing 11 is installed in the center of the body frame 5.
Rotation of the main bearing 12, the upper end surface of the body frame 5 and the motor 3
The thrust ball bearing 13 provided between the lower end surface of the child 3a and
Is supported by the main shaft of the drive shaft 4 at its lower end.
Eccentric bearing 14 (hereinafter referred to as slewing bearing) is provided
I have. The lower end surface of the body frame 5 is made of aluminum alloy.
Fixed scroll 15 is fixed, fixed scroll 15 is spiral
It consists of a fixed scroll wrap 15a and a mirror plate 15b.
At the center of the plate 15b, start winding the fixed scroll wrap 15a.
The discharge port 16 opening to the section is also opened to the discharge chamber 2.
The suction chamber 17 is provided on the outer periphery of the fixed scroll wrap 15a.
Is provided. Form a compression chamber by meshing with the fixed scroll wrap 15a
Swirling orbiting scroll wrap 18a and drive shaft 4
Of the swivel shaft 14b supported by the swivel bearing 14 of the
Aluminum alloy swivel strip consisting of
Crawl 18 is driven by fixed scroll 15 and body frame 5.
It is placed so as to be surrounded by the moving shaft 4 and the outer circumference of the turning shaft 18b.
A sleeve 19 made of high tensile steel material is
The surface of the lap support disk 18c is hardened. Being restrained by the parallel pin 19 fixed to the body frame 5
The thrust bearing 20 that can move only in the axial direction and the fixed
A spacer 21 is provided between the roll 15 and the end plate 15b.
The axial dimension of the spacer 21 depends on the oil film surface of the sliding surface.
The thickness of the lap support disk 18c is about 0.0
It is set large by 15 to 0.020 mm. The bottom of the orbiting bearing 14 of the drive shaft 4 and the orbiting scroll 18 are rotated.
Eccentric bearing space 36 between the end of the rotating shaft 18b and the lap support circle
The outer peripheral space 37 of the plate 18c is the turning shaft 18b and the lap support disc 18
It is communicated by an oil hole A38a provided in c. The thrust bearing 20 has a central portion as shown in FIGS. 2 and 6.
The part is two parallel straight parts 22 and two arcs connected to it
It is pierced into a shape formed by the curved portion 23. The Oldham ring 24 for preventing the orbiting scroll from rotating
Is it a light alloy or resin material suitable for consolidation and injection molding?
And a thin annular plate 24a whose both surfaces are parallel to each other as shown in FIG.
It consists of a pair of parallel key parts 24b provided on one surface of the
The outer contour of the annular plate 24a is composed of two parallel straight line portions 25.
It is composed of two arcuate curved line parts 26 connected to it, and a straight line part
As shown in Fig. 6, the minute 25 is minute in the linear portion 22 of the thrust bearing 20.
It can be engaged and slid in a small gap, and the side of the parallel key portion 24b
The surface 24c is orthogonal to the center of the straight line portion 25, and is shown in FIGS.
Provided on the lap support disk 18c of the orbiting scroll 18 as shown in
Sliding by engaging a pair of key grooves 71 with a minute gap
The shape is set. The inner contour of the annular plate 24a is the outer
It has a shape similar to the contour. Also, the parallel key portion 24b
The dented portion 24d provided at the base also serves as a passage for lubricating oil.
You. As shown in FIGS. 1 and 3, the main body frame 5 and the thrust
A release gap 27 of about 0.1 mm is provided between the bearing 20 and
And the main body frame 5 facing the release gap 27.
An annular groove 28 is also provided in the ring groove, and a rubber sheath surrounding the annular groove 28 is used.
The rule ring 70 connects the body frame 5 and the thrust bearing 20.
It is installed in between. The upper part of the motor chamber 6 and the discharge chamber 2 are on the side of the closed case 1.
Communication via bypass discharge pipe 29 connected through the wall
However, the opening position of the bypass discharge pipe 29 to the motor chamber 6 is fixed.
Bypasses the side of the upper coil end 30 of the determinator 3b and bypasses
Connected to the upper open end of the discharge pipe 29 and the upper surface of the closed case 1.
The discharge pipe 31 is a hole 32 provided in the bearing frame 5,
It is arranged between the upper surface of the closed case 1 and the bearing frame 9.
And punching metal 33 with many small holes
Communicate with each other. The discharge chamber oil sump 34 provided under the motor chamber 6 is
The upper part of the motor chamber 6 and a part of the outer periphery of the stator 3b of the motor 3 are covered
They are communicated by a cooling passage 35 provided as a stack. Also,
The discharge chamber oil sump 34 is an oil hole B38b provided in the body frame 5.
Via the annular groove 28 and the Oldham ring 24
In the back pressure chamber 39 of the orbiting scroll 18 in which the main bearing 12
It is installed in the slewing bearing 14 through the minute gap of the sliding part of
It also communicates with the eccentric bearing space 36 via the oil groove A40a.
You. In addition, the oil hole B38b provided in the body frame 5 is a drive shaft.
4 is provided on the surface of the lower shaft portion 4a corresponding to the lower bearing 11.
The spiral oil groove 41 also leads to the spiral oil groove 41 winding direction.
Uses the viscosity of the lubricating oil when the drive shaft 4 rotates forward.
Provided for screw pump action, the end of which is
The shaft portion 4a is formed partway. As shown in FIGS. 6 and 7, the fixed scroll 15 is a suction chamber.
An arc-shaped suction passage 42 that connects both ends of 17 is provided.
Circular suction hole 43 orthogonal to this is fixed scroll wrap 15
It is also provided at a right angle to the side surface of a and is located at the bottom of the suction hole 43.
The portion reaches the side surface of the suction passage 42 in a plane. 8th
As shown in the figure, the center of the suction hole 43 should be aligned with the bottom surface 44 of the suction passage 42.
The size W45 of the opening to the suction passage 42 is defined by the suction hole 43
Is smaller than the diameter dimension of. Also. Suction hole 43
The suction pipe 47 of the accumulator 46 is connected to the
A suction pipe 47 is provided between the bottom surface 44 of the suction hole 43 and the suction pipe end surface 48.
Inner diameter dimension and suction hole between suction pipe end face 48 and bottom face 44
Larger than depth dimension L49 and larger than opening dimension W45
A check valve 50 made of a circular thin steel plate is arranged. 50 check valve
The surface has poor oil wetting characteristics and Teflon with high elasticity or
It is coated with rubber. In addition, the second compression that does not communicate with the suction chamber 17 or the discharge chamber 2
The chamber 51 and the outer peripheral space 37 are opened to the second compression chamber 51 and the end plate 15 is opened.
The small diameter injection hole 52 provided in b and the end plate 15b
Injection formed with resin heat insulating cover 53
Groove 54, a stepped oil hole C38c opened to the outer peripheral space 37
Oil passage C38c
The large-diameter portion 56 has a notch in a part of the outer circumference as shown in FIG.
Check valve 58 and coil spring 59 made of sheet steel with a slot 57
And are arranged to form a check valve device 58a. Koi
The le spring 59 is pressed against the heat insulating cover 53 and the check valve 58 is
Always energize. Opening position of oil hole C38c to outer peripheral space 37
Communicates with the discharge port 16 as shown in FIGS. 10 and 11.
The volume reduction process of the third compression chambers 60a, 60b is completed (discharge
Near the port 16 and immediately before the third compression chamber 60a, 60b opens)
When the orbiting scroll 18 has moved to (see Fig. 10),
The outer peripheral space 37 communicates with the oil hole C38c, and the other discharge ports
The volume of the third compression chamber 60a, 60b communicating with the port 16 is the largest
When the lap support disk 18c
It is provided at a position where it is blocked. In FIG. 12, the horizontal axis represents the rotation angle of the drive shaft 4,
The vertical axis shows the refrigerant pressure, which is used in the intake, compression, and discharge processes.
The pressure change state of the refrigerant gas is shown, and the solid line 62 indicates normal pressure.
The change in pressure during rotation is indicated by the dotted line 63 during abnormal pressure increase operation.
Indicates pressure change. In FIG. 13, the horizontal axis represents the rotation angle of the drive shaft 4,
The vertical axis indicates the refrigerant pressure, and the solid line 64 indicates the discharge chamber 2 as well as the suction chamber 17.
Injection into the second compression chambers 51a, 51b that do not communicate with
The change in pressure at the opening positions of holes 52a and 52b is shown by the dotted line 65
Is the first compression chamber 61a, 61b communicating with the suction chamber 17 (see FIG. 6).
Shows the pressure change at a fixed point, and the alternate long and short dash line 66 indicates discharge.
Pressure at a fixed point of the third compression chamber 60a, 60b communicating with chamber 2
The two-dot chain line 67 indicates the change and the first compression chambers 61a, 61b and the second pressure
It shows the pressure change at a fixed point between the compression chambers 51a and 51b.
The emphasis line 68 shows the pressure change in the back pressure chamber 39. Regarding the scroll refrigerant compressor configured as described above,
The operation will be described. 1 to 13, the drive shaft 4 is driven by the motor 3
When is driven to rotate, the orbiting scroll 18 makes an orbiting motion,
Suction containing lubricating oil from the refrigeration cycle connected to the compressor
The refrigerant gas is a suction pipe 47 connected to the accumulator 46,
It flows into the suction chamber 17 through the suction hole 43 and the suction passage 42 in order, and
Formed between the scroll 18 and the fixed scroll 15
The first compression chambers 61a and 61b are used to confine them inside the compression chambers.
The second compression chambers 51a, 51b and the third compression chambers 60a, 6 which are time-closed spaces
It is sequentially transferred to 0b, compressed and passed through the discharge port 16 in the center.
It is discharged into the discharge chamber 2. Discharged refrigerant gas containing lubricating oil
Through the bypass discharge pipe 29 connected to the outside of the compressor.
After returning to the motor room 6 in the compressor and the compressor,
Is discharged from the discharge pipe 31 into the motor but flows into the motor chamber 6.
The side surface of the upper coil end 30 of the motor 3
Of the lubricating oil by attaching to the surface of the motor winding.
A hole made in the bearing frame 9 after partly separated
When passing 32, change the flow direction or punching metal
When the oil passes through the small hole of
The throat effectively separates the lubricating oil. Part of the lubricating oil separated from the discharge gas is
After lubricating the sliding surface, cool the cooling passage 35 with the remaining lubricating oil.
As shown in the figure, while cooling the motor 3, the oil is collected in the oil reservoir 34 in the lower discharge chamber.
Gathered. The lubricating oil in the discharge chamber oil sump 34 is the surface of the lower shaft portion 4a of the drive shaft 4.
By the screw pump action of the spiral oil groove 41 provided on the surface,
Oil is supplied to the thrust ball bearing 13 and the end of the lower shaft 4a is
When lubricating oil passes through the bearing gap, the oil film seals
Depending on the application, the discharge refrigerant gas atmosphere of the motor chamber 6 and the main bearing 12
The upstream space of is cut off. Lubricating oil containing the dissolved discharge refrigerant gas of the discharge chamber oil sump 34,
When passing through the minute gap of the main bearing 12, discharge pressure and suction pressure
The pressure is reduced to an intermediate pressure and flows into the back pressure chamber 39.
After that, the oil groove A40a of the slewing bearing 14, the eccentric bearing space 36, the slewing disc
It flows into the outer peripheral space 37 through the oil hole A38 passing through the roll 18.
You. Furthermore, the cooling from the third compression chamber 60a, 60b to the discharge port 16
At the start of the medium gas discharge, the oil hole C is
38c is in the open state, and drive shaft rotation at point K in Fig. 13
As shown by the rolling angle, in each compression chamber, the hydraulic pressure is
There is no possibility of contraction and the pressure in the second compression chamber 64 is low
It is in. Therefore, the oil hole C38c,
After passing through the injection groove 54 and the injection holes 52a and 52b
It smoothly flows into the second compression chambers 51a, 51b with a large pressure difference,
Lubricate the sliding surface in the middle of the passage. In addition, the discharge chamber oil sump 34 is connected to the annular groove 28 and the release gap 27.
Since the thrust bearing 20 is
It is urged and is in contact with the end surface of the spacer 21. Also, the lap support disk 18c of the orbiting scroll 18 is
There is a slight gap between the last bearing 20 and the end plate 15b of the fixed scroll 15.
Holds a small gap and slides smoothly, and the fixed scroll
Between the end face of the roll wrap 15a and the lap support disc 18c,
Between the end face of the orbiting scroll wrap 18a and the end plate 15b.
The gap between the two is also kept small and the refrigerant gas between the adjacent compression chambers
Reduce leaks. Injection holes 52a, 52b opening of the second compression chambers 51a, 51b
Pressure changes 64 as shown in Fig. 13, and the pressure in the discharge chamber 2
It is instantaneously higher than the back pressure chamber pressure 68 which changes following the.
However, since the average pressure is low, the lubricating oil from the back pressure chamber 39
It will flow into the second compression chambers 51a, 51b intermittently and back pressure during normal operation
The pressure in the second compression chambers 51a, 51b, which is instantaneously higher than the chamber pressure 68,
The condensed refrigerant gas is reduced by the small diameter injection holes 52a, 52b.
Declined and instantaneous backflow to the injection groove 54 was small.
None, and when the compression stroke of the second compression chambers 51a, 51b progresses
Oil hole C38c is closed by lap support disc 18c
Therefore, backflow from the second compression chambers 51a, 51b to the outer peripheral space 37 is also possible.
Does not occur. Lubricating oil injected into the second compression chambers 51a, 51b
Joins the lubricating oil that has flowed into the compression chamber together with the suction refrigerant gas.
Then, seal the minute gap between the adjacent compression chambers with an oil film.
Prevents compressed refrigerant gas leakage and does not lubricate sliding surfaces between compression chambers.
The compressed refrigerant gas is discharged again into the discharge chamber 2. The lubricating oil differentially supplied to the back pressure chamber 39 is
The urging force of the intermediate pressure is swiveled with the elastic force of the ring 70.
Of the lap support disk 18c and the end plate 15b by acting on the mirror 18
The pressure oil film is sealed on the moving surface to create a space between the outer peripheral space 37 and the suction chamber 17.
Between the thrust bearing 20 and the lap support.
The gap between the sliding surface with the holding disk 18c is also lubricated and sealed. For a while after the cold start of the compressor,
As can be understood from FIG. 13, the pressure in the discharge chamber 2 is the second compression.
The pressure of the refrigerant gas, which is lower than the pressure in the chambers 51a and 51b and is being compressed,
From the second compression chamber 51a, 51b through the injection passage 55
It tries to flow back into the back pressure chamber 39, but the check valve 58
However, backflow to the outer peripheral space 37 is prevented, and the discharge chamber oil sump 34
As the lubricating oil rises in pressure in the discharge chamber 2, the back pressure chamber 39 and the outer peripheral space become empty.
Differential pressure is replenished up to 37. Therefore, the back pressure on the thrust bearing 20 at the initial stage of cold start is
The urging force is generated by the pressure in the compression chamber, and
The thrust load that tries to separate from the constant scroll 15
While thrusting, the thrust bearing 20 retreats slightly and swivels.
The axial clearance between the scroll 18 and the fixed scroll 15
You. Such axial bearing 20 axial compliance
The mechanism causes leakage in the compression space and reduces the pressure in the compression chamber.
And reduce the compression load in the initial stage of starting. Then, as the pressure in the discharge chamber 2 increases, the outer peripheral space 37
The lubricating oil resists the urging force of the coil spring 59 and
Injection holes 52a, 52b into the second compression chambers 51a, 51b.
Be cut. In addition, the oil injection
Pressure in case of instantaneous liquid compression due to
The pressure in the constriction chamber is an abnormal pressure rise as shown by the dotted line 63 in Fig. 12.
Overcompression occurs, but the discharge chamber 2 and high-pressure space communicating with it
Since the volume is large, the rise in discharge chamber pressure is extremely small. In addition, the liquid communication is used to communicate with the second compression chambers 51a and 51b.
The abnormal pressure rises in the injection groove 54, etc.
Due to the throttling effect of the oil hole C38c and the check valve 58
The space 37 and the injection groove 54 are shut off from each other. If there is a tracking delay in the check function of the check valve 58,
There is also a wrap support disk 18c that closes the oil hole C38c.
Help with this. On the contrary, wrap the oil hole C38c
The non-return action of the check valve 58 when the holding disk 18c is not blocked.
Function to help each other's weaknesses
To prevent backflow to the back pressure chamber 39. As a result, the pressure in the back pressure chamber 39 does not change, and the thrust bearing 20
There is no change in the back pressure urging force that acts on the back of the. Accordingly
During liquid compression, the excessive amount of force acting on the orbiting scroll 18
The thrust force causes the thrust bearing 20 to
Withdrawal, the pressure in the compression chamber drops, and then normal operation continues
You. It should be noted that the thrust bearing 20 retracts during liquid compression.
Therefore, the pressure in the compression chamber is halfway as shown by the alternate long and short dash line 63a in FIG.
Step down. After the compressor is stopped, the orbiting scroll 18
Reverse swing torque is generated in the
The discharged refrigerant gas flows back to the suction side. Of this discharged refrigerant gas
Following the reverse flow, the check valve 50 moves from the position shown in FIG. 6 to the position shown in FIG.
Position, Teflon coating applied to the surface of the check valve 50
Seals the end face 48 of the suction pipe to prevent the reverse flow of the discharge refrigerant gas.
It stops, the reverse rotation of the orbiting scroll 18 stops, and the intake passage
The space between 42 and the discharge port 16 holds the discharge pressure. Also, with the check valve 58 in the injection passage as the boundary,
The passage communicating with the compression chamber has the discharge pressure, but the outer space
The space between 37 and the back pressure chamber 39 is kept at an intermediate pressure for a while.
Hold and gradually increase due to a slight inflow of lubricating oil from the oil reservoir 34 in the discharge chamber.
Approaches the discharge pressure. Orbiting scroll when the compressor is stopped 18
Reverses and stops at the expanded position of the third compression chamber 60a, 60b
However, the opening of the oil hole C38c to the outer peripheral space 37 is lap supported.
It is blocked by the disc 18c. After the compressor is stopped, the coil sp
The check valve 58 is also injected by the urging force of the ring 59.
Since it shuts off the passage 55, the space from the outer peripheral space 37 to the compression chamber
There is no inflow of lubricating oil. In addition, this scroll refrigerant compressor is installed in the refrigeration cycle.
Intake immediately after switching from heating operation to defrosting operation
Side becomes high pressure and discharge side becomes low pressure. However,
From the compression chamber to the outer space 37
It is possible to prevent the reverse flow of the refrigerant gas to the. Further, in the above embodiment, the lubricating oil in the discharge chamber oil sump 34 is constantly maintained.
Oil injection into the second compression chambers 51a and 51b, which are closed spaces.
However, if there is always a compressed space without a closed space,
The same is true. Also, depending on operating conditions such as compressor operating speed and pressure,
In the first compression chamber 61a, 61b leading to the suction chamber 17 or the suction chamber 17
Even when oil is injected, the action of the check valve 58 causes the first compression chamber to operate.
Refrigerant gas from 61a, 61b or suction chamber 17 to outer peripheral space 37
Backflow can be prevented. In the above embodiment, the stepped shape having the small diameter portion is used.
Secure the oil hole C38c, check valve 58 and coil spring 59
Although it was installed on the end plate 15b of the roll 15,
It may be provided on the rotating shaft 18b or the lap supporting disk 18c. In this configuration, due to the abnormal pressure rise in the compression space,
Therefore, the refrigerant gas flows backward from the compression space to the outer peripheral space 37.
However, the check valve action prevents the backflow to the back pressure chamber 39.
It is possible to prevent the lubricating oil from flowing out of the back pressure chamber 39 and the discharge chamber oil sump 34.
You. Further, the refrigerant gas flows backward from the compression space to the outer peripheral space 37.
As a result, the pressure in the outer peripheral space 37 also rises and thrust
The bearing 20 is retracted to the side opposite to the compression chamber. As a result,
Roll 18 is easily separated from fixed scroll 15 in the axial direction
The axial clearance in the compression chamber expands and the compression chamber clearance is released.
So the thrust bearing 20 axial compliance machine
It can also assist the quick operation of the structure. Further, in the above embodiment, the discharge chamber oil sump 34 and the back pressure chamber 39 are
From the discharge chamber oil sump 34, communicating through a minute gap in the main bearing 12
The lubricating oil was depressurized to keep the back pressure chamber 39 at an intermediate pressure.
Compressor usage conditions (compressor load and operating speed range vary greatly)
Depending on the threshold, etc., the oil provided on the body frame 5
In the passage branched from the hole B38b, the discharge chamber oil sump 34 and the back pressure chamber 39
The back pressure chamber 39 can be made to correspond to the discharge pressure by directly communicating with. Further, in the above embodiment, the eccentric bearing is provided at the tip of the drive shaft 4.
Although the slewing bearing 14 in the form of providing the space 36 is provided, FIG.
As shown in Fig. 15, the eccentric bearing space is installed in the orbiting scroll.
In the case of bearings that form a swivel bearing with the drive shaft
Also exhibits the same actions and effects as described above. Further, in the above embodiment, the refrigerant compressor has been described.
But use other lubricants such as oxygen, nitrogen, helium and other
Similar effects can be expected in the case of a gas compressor. As described above, according to the present invention, the main bearing 12 that supports the drive shaft 4 is used.
Between the body frame 5 and the fixed scroll 15
18 times scroll 18 is placed, orbiting scroll 18 wrap
The support disc 18c supports the wrap support disc 18c on the side opposite to the compression chamber.
In order to do so, the thrust bearing 20 provided on the main body frame 5 and the
A fine film that can form an oil film between the fixed scroll 15 and the end plate 15b.
It is arranged with a small gap, and the thrust bearing 20
End plate 15b and body frame 5 to accommodate the support disc 18c.
The pressure from the discharge chamber oil sump 34 which is formed by
The outer space 37, which is physically isolated, is placed and the wrap support is
Partitioned from thrust bearing 20 on the side opposite to the compression chamber of holding disk 18c
The back pressure chamber 19 of the orbiting scroll 18 to the main bearing 12
Adjacent to each other, the discharge chamber oil sump 34 and the compression space are the back pressure chamber 39 and
The differential pressure oil supply passage that sequentially passes through the outer peripheral space 37
A back pressure chamber 39 is provided in the middle of the oil passage between the pressure chamber 39 and the outer peripheral space 37.
Non-return valve device 58a that allows only inflow from the outer peripheral space 37
In the configuration where the
Install the thrust bearing 20 between the bearing 20 and the body frame 5.
A biasing means for biasing the fixed scroll 15 is provided to rotate the scroll.
The orbiting scroll 18 has a fixed scroll 15 and a thrust bearing 20.
Between them, there should be at least an axial minute gap where an oil film can be formed.
The thrust bearing 20 has a swivel scroll to be arranged.
Ruler 21 that regulates the range of movement to the side of
Axial compliance mechanism of the strike bearing 20
The pressure in the partial space 37 biases the thrust bearing 20 toward the side opposite to the compression chamber.
Therefore, part of the wall surface of the outer peripheral space 37 is installed in the thrust bearing 20.
As a result, the lubricating oil in the discharge chamber oil sump 34 is
Via the space 37 into the compression space consisting of the suction chamber 17 and the compression chamber
As it is supplied, the slurry in the outer peripheral space 37 on the way
Lubrication and compression chamber clearance on the sliding contact surface between the strike bearing 20 and the end plate 15b
Can be oil film sealed. Thereby the frictional resistance
Reduces gas leakage during compression, reduces input and improves durability
And the compression efficiency can be improved. In addition, the compressed air rises abnormally and the gas in the compression space
Tries to flow backward toward the back pressure chamber 39 and the discharge chamber oil sump 34.
At this time, the check valve device 58a acts to prevent gas backflow to the back pressure chamber 39.
Block, thereby back pressure chamber 39 and main bearing 12 and discharge
Prevents the lubricating oil from flowing out of the chamber oil sump 34 and improves the durability of the main bearing 12.
And obtaining the effect of differential pressure lubrication to the compression space described above
Can be. Moreover, in particular, the thrust increases due to the pressure increase in the outer peripheral space 12.
The back pressure of the bearing 20 is promoted to promote the backward movement to the side opposite to the compression chamber.
Since the pressure rise in the chamber 39 can be prevented, abnormal pressure in the compression space
Ascend to move axially away from the fixed scroll 15
The swivel scroll 18 moves quickly,
Early overcompression can be reduced by early release of intersealing. Further, according to the present invention, the back pressure chamber 39 and the outer peripheral space 37 are connected to each other.
Pass the oil passage through the center of the lap support disc 18c.
Through the oil hole 18a having a throttle passage extending from
The outer peripheral space 37 side from the throttle passage in the middle of the oil hole 18a
By arranging the check valve device 58a in the
Can be placed long. This stabilizes the passage resistance to the compression space.
It is possible to prevent excessive or insufficient refueling. Also, check valve
It is possible to speed up usage and improve reliability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical cross-sectional view of a scroll refrigerant compressor according to an embodiment of the present invention, FIG. 2 is an exploded view of main parts of the compressor, and FIG. 3 is thrust in FIG. FIG. 4 is a detailed partial cross-sectional view of the seal portion of the bearing, FIG. 4 is an external view of an Oldham ring in the compressor, FIG. 5 is an external view of the Oldham mechanism assembly relating to FIG. 1, and FIG. FIG. 7 is a sectional view taken along line A, FIG. 7 is an explanatory view of the position of the check valve in the suction pipe connecting portion in FIG. 6, FIG. 8 is a partial sectional view taken along line BB in FIG. 7, and FIG. Fig. 10 is an external view of the check valve used in the oil injection passage of the compressor, Fig. 10 and Fig. 11 are explanatory views of the movement of the compression chamber near the discharge port of the compressor, and Fig. 12 is the discharge from the suction stroke of the compressor. Characteristic diagram showing the pressure change of the refrigerant gas up to the stroke, Fig. 13 shows each compression chamber Kicking characteristic diagram showing a pressure change in the fixed point, FIG. 14, FIG. 15 is a longitudinal sectional view of a different conventional scroll compressor. 2 ... Discharge chamber, 3 ... Motor, 4 ... Drive shaft, 5 ... Main frame, 12 ... Main bearing, 15 ... Fixed scroll, 15
a: Fixed scroll wrap, 15b: End plate, 16 ... Discharge port, 17 ... Suction chamber, 18 ... Orbiting scroll, 18a ...
… Orbiting scroll wrap, 18c …… Wrap support disc, 34
…… Discharge chamber oil sump, 39 …… Back pressure chamber, 52a, 52b …… Injection hole, 54 …… Injection groove, 55 …… Oil injection passage, 58 …… Check valve, 58a …… Check valve device, 59 …… Coil spring.

Claims (1)

(57) [Claims] The orbiting scroll wrap 18a on the lap support disc 18c forming a part of the orbiting scroll 18 is rockingly rotated with respect to the spiral scroll-shaped fixed scroll wrap 15a formed on one surface of the end plate 15b forming a part of the fixed scroll 15. The fixed scroll wrap 15 can be freely engaged with each other to form a spiral compression space composed of a suction chamber 17 and a compression chamber between the scrolls.
A discharge port 16 is provided at the center of a, the suction chamber 17 is provided outside the fixed scroll wrap 15a, and the compression space is formed by a plurality of the compression chambers that continuously move from the suction side toward the discharge side. A scroll compression mechanism for compressing a fluid is formed, the scroll compression mechanism and the motor 3 are housed in the closed case 1, and the drive shaft 4 connected to the motor 3 is supported to drive the orbiting scroll 18 to orbit. Main body frame 5 having main bearing 12 and said fixed scroll 15
The orbiting scroll 18 is disposed between the wrap support disc 18c and the lap support disc 18c, and the lap support disc 18c is provided with the thrust bearing 20 and the end plate 15b provided on the main body frame 5 to support the wrap support disc 18c on the side opposite to the compression chamber. Is formed with a minute gap capable of forming an oil film between the end plate 15b and the main body frame 5 to accommodate the lap support disk 18c at the outer peripheral portion adjacent to the thrust bearing 20. Discharge chamber oil reservoir
An outer peripheral space 37 that is pressure-isolated from 34 is arranged, and the orbiting scroll 18 is provided on the side opposite to the compression chamber of the lap support disk 18c and inside the thrust bearing 20.
A back pressure chamber 39 is provided adjacent to the main bearing 12, and the discharge chamber oil reservoir 34 and the compression space communicate with each other through a differential pressure oil supply passage that sequentially passes through the back pressure chamber 39 and the outer peripheral space 37. , The back pressure chamber
The back pressure chamber is provided in the middle of the oil passage between the outer peripheral space 37 and the outer peripheral space 37.
In the structure in which the check valve device 58a that allows only the inflow from 39 to the outer peripheral space 37 is arranged, between the thrust bearing 20 and the main body frame 5 that are movable in the axial direction,
An urging means for urging the thrust bearing 20 in the direction of the fixed scroll 15 is provided, and the orbiting scroll 18 is provided between the fixed scroll 15 and the thrust bearing 20 so that at least an axial minute gap capable of forming an oil film. The thrust bearing 20 is provided with an axial compliance mechanism of the thrust bearing 20 provided with means 21 for restricting the range in which the thrust bearing 20 moves toward the orbiting scroll 18, so that the outer peripheral space 37 A scroll gas compressor in which the thrust bearing 20 constitutes a part of the wall surface of the outer peripheral space 37 so that the pressure urges the thrust bearing 20 toward the side opposite to the compression chamber. 2. An oil passage communicating between the back pressure chamber 39 and the outer peripheral space 37,
A check valve is provided in the lap support disk 18c via an oil hole 18a having a throttle passage extending from the center side to the outer peripheral side, and is located closer to the outer peripheral space 37 than the throttle passage in the middle of the oil hole 18a. The scroll gas compressor according to claim 1, further comprising a device 58a.